Tobacco leaf conditioner

ABSTRACT

In this invention a tobacco leaf is unraveled by subjecting it to a flow of air that moves across the leaf transversely from its stem to its edges while the leaf is constrained along its stem. There is also provided a first air permeable belt and two divergent air permeable belts which cooperate with suction chambers to flatten and stretch the leaf. Selective control is obtained when manipulating the suction values and speed differential of the belts.

[54] TOBACCO LEAF CONDITIONER 2,180,368 11/1939 Rundelletal.............l3l/l24 Bush.................,......L.131/123 131/123 [72] Inventor: Frank Hollenton, Richmond, Va.

[73] Assignee: AMF Incorporated Baughan....................

20 O0 99 ll 2 11 74 51 34 6. 76

Oct. 1, 1970 Primary Examiner-Samuel Koren Assistant Examiner-J. F. Pitrelli [21] App]. No.: 77,135

[22] Filed:

Attorney-George W. Price and Eli Weiss 131/123 ABSTRACT A24) 5/14 In this invention a tobacco leaf is unraveled by sub- 131/147 A jecting it to a flow of air that moves across the leaf transversely from its stem to its edges while the leaf is -constrained along its stem. There is also provided a 521 u.s.c|...............................131/147R, [51] 5s FieldofSearch.'..... ,123,124,

[56] References Cited UNITED STATES PATENTS first air permeable belt and two divergent air permeable belts which cooperate with suction chambers to flatten and stretch the leaf. Selective control is obm S e .m a V n .m m m m. s m. e m h. .m t u m m n D -ub .m 9 u .m .m m1 .m mm C t n 7 he ma wm d m e mm R R ,7nu7 4 4 1 1 33/ l ll 3 u 3 1 n hdflam tt Dee" mHHm eer hdd mnnfl uua wRRc 246 7339 9998 1111 06 7 l l P'ATENIED um 24 I972 SHEET 2 BF 4 INVENTOR FRANK HOLLENTON ATTORNEY PATENIEnnm 24 I972 3 6 97 snm 3 0F 4 FIG. 4

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INVENTOR.

w! a I .BY FRANK HOLLENTON I I V3 54 um, v

ATTORNEY TOBACCO LEAF CONDITIONER BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates generally to a method and apparatus for processing tobacco leaf and more particularly relates to the automatic unraveling and flattening of a tobacco leaf.

2. Description of the Prior Art Currently, in the manufacture of cigars, the delicate tobacco wrapper leaves are stripped of their stems and collected into pads of leftand right hand half leaves by means of a skilled operator working at a stripping machine. When operating the stripping machine, the operator manually unravels and partially flattens the leaves as they are fed to the machine. The rightand left hand half leaves accumulate within the stripping machine, the right hand half leaves being stacked one upon another to form a right hand stack or book; and the left hand half leaves being stacked one upon another to form a left hand stack or book.

The books of right and left hand half leaves, when they reach sufficient size, are removed from the stripping machine. The book of left hand half leaves are transferred to left hand cigar machines; and, the book of right hand half leaves are transferred to the right hand cigar machines. At the cigar machines, an operator, commonly referred to as the wrapper layer, carefully selects and stretches portions of half leaves over a wrapper die which severs or cuts a strip of tobacco having a desired shape from the half leaf for application to a cigar by a machine. The unused portion of the half leaf is then re-examined by the wrapper layer for possible second or third cuts.

SUMMARY OF THE INVENTION In this invention, there is disclosed apparatus and method for automating the unraveling and flattening of a tobacco leaf. A tobacco leaf is fed into a conditioning chamber where the leaf is unraveled and extended to its full size and shape. The conditioning chamber .can comprise two plates spaced from each other and coupled to a leaf holding means which grips andholds the leaf at a convenient place, for example, along the stem of the leaf, as air is moved transversely across the leaf from its stemtoits edges.

The movement of the air across the tobacco leaf from its stem outward while the leaf is held or 'constrained by its stem causes the leaf to flutter, to become unraveled, and to be extended to its full size and shape.

Thereafter, the leaf is further flattened and stretched in a stretcher-flattener.

The tobacco leaf stretcher-flattener comprises a relatively wide air permeable main belt positioned beneath two divergent air permeable belts. The two divergent belts are driven at substantially the same rate of speed, and the main belt is driven at a rate of speed that can vary somewhat from the speed of the divergent belts.

Individual suction chambers are positioned to cooperate with and effect a controlled flow of air through specific defined areas of each of the various belts.

The unraveled and extended leaf from the conditioning chamber is fed to and pneumatically captured by the advancing relatively wide air permeable main belt and carried to a position beneath the two divergent belts where the leaf is released from the relatively wide main belt and captured pneumatically byv the two divergent air permeable belts.

Each of the divergent belts pneumatically captures a portion of the tobacco leaf by means of suction from a source of suction acting through the divergent air permeable belts, Le, a portion of the right hand side of the leaf being pneumatically captured by one belt, and a portion of the left hand side of the leaf being pneumatically captured by the other belt. The movement of the belts along-their divergent paths causes the leaf that is pneumatically captured by the belts to be stretched.

Thereafter, the leaf is transferred from the divergent belts back to the relatively wide air permeable main belt in a stretched, unwrinkled form. I

The novel features that are considered characteristic of this invention are set forth with particularity in the appended claims. The invention itself, however, both as to its organization and method of operation, will best be understood from the following description whenread in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top plan view of structure in accordance with the principles of the invention;

FIG. 2 is a side view of the structure of FIG. 1; FIG. 3 is a top view of the conditioning chamber; FIG. 4 is a view along the line 44 of FIG. 3; FIG. 5 is a view along the line 5'5 of FIG. 3;

. FIG. 6 is a top view of structure in accordance with the principles of the invention illustrating the conditioning of a tobacco leaf; and

FIGS. 7, 8 and 9 illustrate pictorially various conditions that the tobacco leaf can assume.

Similar reference numbers refer to similar parts throughout the various views of the drawing.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring specifically to FIGS. 1, 3, 4 and 5, there is illustrated a top plan view of structure in accordance with the principles of the invention.

A leaf that is to be opened and unraveled is fed stem end first to a conditioning chamber 10. The conditioning chamber 10 is defined by a top plate 12 parallel to and spaced from a bottom plate 14 by two side end members l6, 18. Each side end member 16, 18 is a hollow closed end duct having a plurality of passageways which extend through the side walls of the ducts which face into the chamber 10. In duct 16, side wall 20 supports a plurality of passageways 22 which extend from the chamber of duct 16 to the chamber 10; and, in duct 18, side wall 24 supports a plurality of passageways 26 which extend from the chamber of duct 18 to the chamber 10.

A source of suction is coupled to each of the ducts 16, 18 and, acting through the ducts and the passageways 22, 26 of each duct, drawsair out of the chamber 10 defined by the top plate12, bottom plate 14 and side walls 20, 24 of end members 16, 18.

The top plate 12 supports a longitudinal slot 28 which passes completely through the plate 12 and extends from the front or upstream end 30 of the chamber 10 to the back or downstream end 32 of the chamber.

In a similar manner, bottom plate 14 supports a longitudinal slot 34 which also passes completely through the plate 14 and extends from the front upstream end 30 of the chamber to the back or downstream end 32 of the chamber. The slot 28 in the top plate 12 and the slot 34 in the bottom plate 14 are sized to have a width that is sufficient to receive, with considerable clearance, a grooved conveyor belt.

Rigid cross members 36, 38, 40 which extend across the top plate 12 and the bottom plate 14 provide a rigid unitary structure. The cross members 36, 38, 40 or the like are required to provide structural integrity which was lost when the longitudinal slots 28, 34 were formed in the top plate and bottom plate.

A first pair of pulleys 42, 44 supports a first grooved belt 46, the lowermost surface of the belt being substantially centrally positioned within the conditioning chamber 10. The pulley 42 is an idler pulley coupled to rotate freely about a shaft 48. The pulley 44 is securely coupled by a pin, set screw or the like to a shaft 50 which is rotatably supported by brackets 52, 54. A drive gear 56 secured rigidly to shaft 50 drives pulley 44 through shaft 50 at a predetermined rate.

The slot 28 is sized to be approximately inch wider than the width of the grooved conveyor belt.

In a similar manner a second pair of rollers 58, 60 supports a second grooved conveyor belt 62 wherein the uppermost surface of the belt 62 is substantially centrally positioned within the conditioning chamber 10. In the conditioning chamber 10, the two belts 46, 62 can be positioned to lightly contact each other. Each belt 46, 62 supports a groove in its outer surface, the two grooves being provided to accommodate the stern of a tobacco leaf.

The pulley 58 is an idler pulley coupled to rotate freely about a shaft 64 which, in turn, is retained in position by a bracket member 68. The pulley 60 is coupled securely by a pin, set screw or the like, to a shaft 70 rotatably supported by a bracket 72. b

r A drive gear 74 coupled rigidly to shaft 70 drives pulley 60 through shaft 70 at a predetermined rate. A shaped feed plate 76 is coupled to the upstream end of the chamber 10 to facilitate the feeding of tobacco leaves into the conditioning chamber 10.

The slot 34 is approximately k of an inch wider than the belt 62, and the belt 62 is centrally positioned relative to the slot.

The drive gears 56, 74 are coupled to a common drive means and are driven at the same rate of speed but in opposite direction. In this manner, a tobacco leaf that is fed to the conditioning chamber 10 is gripped between the two belts 46 and 62 and is advanced through the conditioning chamber. It is to be noted that within the conditioning chamber 10, the belts 46 and 62 are moving in the same direction and at the same rate of speed.

At the downstream end 32 of the conditioning chamber 10, there is a relatively wide air permeable main conveyor belt 78. The upstream end of the main conveyor belt 78 is positioned at the downstream end of the conditioning chamber and is positioned to receive tobacco leaves as they emerge from the conditioning chamber l0.

The main conveyor belt 78 is positioned around two cylindrical members 80, 82. Cylindrical member 80 is coupled to rotate freely about a support shaft and cylindrical member 82 is secured rigidly to a shaft 84coupled tobe rotatably driven at a predetermined rate and in a given direction. The very top surface of the main conveyor belt 78 is aligned with the uppermost surface of the belt 62.

A chamber 86 interposed between the cylindrical members 80, 82 and positioned immediately beneath the top surface of the main conveyor belt 78 supports a plurality of cut-outs arranged in a specific predetermined configuration or pattern in its top surface. The chamber 86 is coupled to a source of suction to create a flow of air through the cut-outs into the chamber 86. The arrangement or array of the cut-outs in the chamber 86 determines the pattern of the relatively wide air permeable main conveyor belt 78 that is exposed to suction. It is to be noted that as the belt 78 is driven over the fixed camber 86, the defined pattern or configuration of suction as defined by the cut-outs in the chamber 86 is progressively exposed to new upstream portions of the moving belt.

Positioned above the relatively wide air permeable main conveyor belt 78 are two diverging air permeable belts 88, 90. Belt 88 is positioned around two cylindrical members 92, 94 wherein cylindrical member 92 is coupled to rotate freely about a shaft and cylindrical member 94 is secured rigidly to a shaft that is rotatably driven at a predetermined rate in a given direction. In a like manner, belt is positioned around two cylindrical members 96, 98. Cylindrical member 96 is coupled to rotate freely about a shaft; and, cylindrical member 98 is secured rigidly to a shaft that is rotatably driven at a predetermined rate and in a given direction.

The divergent belts 88, 90 are coupled to be driven at the same speed. The speed of the belts 88, 90 can be equal to, slightly less, or slightly greater than the speed at which the relatively wide air permeable main conveyor belt is driven.

A chamber 100 interposed between the cylindrical members 92, 94 and positioned immediately above the bottom surface of the diverging belt 88 is coupled to a source of suction and supports a plurality of passageways arranged in a specific predetermined pattern or configuration in its bottom surface. Suction within the chamber 100 creates a flow of air through a defined configuration of that portion of belt 88 that is positioned over the pattern of passageways. Thus, as the belt 88 is driven past the pattern of passageways in the chamber 100, new upstream portions of the belt are continuously exposed to a flow of air through the air permeable belt.

In a like manner, a chamber 102 interposed between the cylindrical members 96, 98 and positioned immediately above the bottom surface of the diverging belt 90 is coupled to a source of suction and supports a plurality of passageways arranged in a specific predetermined pattern or configuration in its bottom surface such that suction within the chamber 100 will create a flow of air through a defined area of the lower portion of belt 90. Thus, as the belt 90 is driven past the passageways in the chamber 102, new upstream portions of the belt 90 are continuously being exposed to the stationary passageways and, therefore, a flow of air through the air permeable belt.

divergent belts 88, 90 and the main belt 78 are each driven in a direction such that the uppermost portion of main belt 78 and the lowermost portions of divergent belts 88, 90 move in the same general direction, that being away from the chamber 10.

' In operation, a leaf is fed, stem end first, over the feed plate and into the'conditioning chamber 10. The stem of the leaf is captured between the first and second grooved conveyor belts 46, 62, and the leaf moves through the conditioning chamber from the upstream end 30 to the downstream end 32.-Each of the two side end members 16, 18 is coupled to a source of suction which, acting through the passageways 22, 24 causes air to be sucked through the longitudinal slot 28 and to flow over the top surface of the leaf from the stem laterally outward to the leaf edges. Thus, the air flowing over the top surface of the leaf forms two streams, one that flows to and through passageway 24 and the other that flows to and through passageway 22. In a similar manner, the suction, acting through passageways 22, 24 causes air to flow through the longitudinal slot 34 and to flow across the. bottom surface of the leaf from the stem laterally outward to the leaf edges. The air sucked into chamber 10 through slot 34 also divides itself into two streams, one flowing to and through passageway 22, and the other through passageway 24.

Thus, as the leaf is held captive along its stem portion only by the grooved conveyor belts 46, 62, it is moved through the conditioning, chamber 10. As the leaf progresses through the chamber 10, the air entering the chamber 10 through the longitudinal slot 28 flows over and across the top surface of the captured leaf; and the air entering the chamber 10 through the longitudinal slot 34 flows over and across the bottom surface of the captured leaf.

The movement of the air laterally outward across the leaf from the stem to the edges across the top and bottom surfaces of the leaf causes the leaf to flutter and to become unraveled and essentially free of folds and overfolds. Additionally, it appears that the fluttering and flexing that the leaf is subjected to in the conditioning chamber actually increases the pliability of the leaf.

As the leaf leaves the conditioning chamber in its unraveled condition, it is pneumatically captured by the upstream end of the relatively wide air permeable main conveyor belt 78 by suction from the chamber 86 acting through the pattern of passageways in the chamber 86 and through the air permeable conveyor belt 78.

The belt 78 can be driven at substantially the same speed or slightly greater than the speed of the belts 46, 62 to minimize subjecting the leaf to being bunched or stretched as it is being transferred from between the belts 46, 62 to the air permeable conveyor belt 78.

If required, a grooved belt 104 can be provided to contact the top surface of the main conveyor belt 78 and continue the guidance of the leaf by maintaining the stem of the tobacco leaf centrally positioned relative to the belt 78.

As the belt 78 is advanced, the leaf suctionally held by the belt 78 approaches the upstream end of the divergent belts 88, 90. At a position slightly downstream from the upstream end of the divergent belts, the suction to the leaf through the belt 78 is reduced for those parts of the leaf that are in contact with the divergent belts 88, and suction is now applied to the leaf through the divergent belts 88, 90. As the belt 78 and the divergent belts 88, 90 advance, the leaf will be stretched. At some point downstream, after the leaf has been stretched as desired, the suction throughthe two divergent belts will be reduced to zero and release the leaf. At the same time, the suction to the leaf through the belt 78 will be increased. Thus, the leaf will then be transferred from being stretched by the divergent belts to the main conveyor belt 78 in a stretched condition.

In the operation of the invention, it has been found that good results are obtained in transferring the leaf from the conditioning compartment to the belt 78 when the belt 78 is advanced at a rate that is slightly greater than the rate of advance of the belts 46, 62. Continuing, the stretching and flattening of the tobacco leaf through the action of the two divergent belts 88, 90 and the main belt 78is determined, to a large degree, by the rate of advance of the divergent belts 88, 90 relative tov the rate of advance of the main belt 78. Referring to FIGS. 7, 8 and 9, V represents the velocity of thebelt 78, V represents the velocity of the divergent belts 88 and 90 (where the velocity of the two belts are equal) and V represents the component of velocity of the divergent belt along the direction of travel of belt'78 as represented by V In those instances where the velocity of the divergent belts is such that V V as illustrated in FIG. 7, the leaf willexperiencea stretch that is dominantly perpendicular to the stem of the leaf.

In those instances where the velocity of the divergent belts is such that V is greater than V as illustrated in FIG. 8, the leaf will experience a stretch that is dominantly divergent backwards relative to the movement of the belt 78.

In those instances where the velocity of the divergent belts is such that V is less than V as illustrated in FIG. 9, the leaf will experience a stretch that is dominantly divergent forward relative to the movement of belt 78.

Thus, in this invention, a tobacco leaf is opened, unraveled, straightened, flattened and stretched. The leaf is opened, unraveled and stretched out in a lateral direction perpendicular to the leaf stem in the conditioning chamber. The leaf is then pulled longitudinally and laterally by controlling the speed of the main belt 78 relative to the speed of the divergent belts 88, 90. The longitudinal and lateral pull exerted by the divergent belts 88, 90 and the main belt 78 is also determined by the amount of suction that is applied to each of the belts. By manipulation of the suction values to the various belts and the speeds at which the various belts are driven, the leaf can be stretched to any degree and in any direction desired. Thus, not only can the leaf be flattened, but it can be flattened to assume a more desirable shape for possible improvement in the vein pattern.

Obviously, many modifications and variations of the present invention are possible in the light of the above teaching. It is, therefore, to be understood that the invention may-be practiced otherwise than as specifically described herein.

' What is claimed is:

l. A tobacco leaf unraveling and flattening device which comprises:'

a first air permeable belt positioned to receive a tobacco leaf on the surface thereof, two air permeable belts mounted in opposed spaced facing relationship with the first air permeable belt and positioned to engage the tobacco leaf on the surface of the first air permeable belt, said two air permeable belts being angularly disposed with respect to said first air permeable belt such that they diverge from said first air permeable belt and to each other, and

suction chambers coupled to said first air permeable belt and said two divergent belts to pneumatically capture the tobacco leaf between the belts and stretch the leaf as the belts are driven.

2. Apparatus according to claim 1, further comprising a leaf conditioning device mounted at the leading end of said first air permeable conveyor.

3. A tobacco leaf unraveling and flattening device according to claim 2 wherein the leaf conditioning device includes a chamber having a top, bottom and first and second side surfaces, means to engage a tobacco leaf by its stem for positioning within the chamber with one side of the leaf facing the top of the chamber, the other side of the leaf facing the bottom of the chamber, and the side edges of the leaf facing the side surfaces of the chamber, a first passageway passing through the top of the chamber, a second passageway in said first side surface, and a third passageway in said second side surface whereby air is caused to enter the chamber through the first passageway and flow transversely across one side of the leaf from the stem to each of the edges and out through the second and third passageways when suction is coupled to said second and third passageways.

4. The structure of claim 3 including a fourth passageway passing through the bottom of the chamber whereby air is caused to enter the chamber through the fourth passageway and flow transversely across the other side of the leaf from the stem to each of the edges and out through the second and third passageways when suction is coupled to, said second and third passageways.

5. The structure of claim 4 wherein said means to engage a tobacco leaf by its stem comprises a first belt having a groove in its outer periphery to engage the stem on one side of the leaf and a second belt having a groove in its outer periphery to engage the stem on th other side of the leaf.

6. The structure of claim 1 including a belt having a groove in its outer periphery mounted between said two air permeable belts to engage the stem on one side of the leaf when said leaf is positioned on said first air permeable belt.

7. The structure of claim 6 including means to drive said two divergent air permeable belts at the same predetermined speed and means to drive said first air permeable belt at a redetermined speed whereby the component of spec of each of the two divergent air permeable belts in the direction of travel of the first air permeable belt is at least equal to the speed of the first air permeable belt. 

1. A tobacco leaf unraveling and flattening device which comprises: a first air permeable belt positioned to receive a tobacco leaf on the surface thereof, two air permeable belts mounted in opposed spaced facing relationship with the first air permeable belt and positioned to engage the tobacco leaf on the surface of the first air permeable belt, said two air permeable belts being angularly disposed with respect to said first air permeable belt such that they diverge from said first air permeable belt and to each other, and suction chambers coupled to said first air permeable belt and said two divergent belts to pneumatically capture the tobacco leaf between the belts and stretch the leaf as the belts are driven.
 2. Apparatus according to claim 1, further comprising a leaf conditioning device mounted at the leading end of said first air permeable conveyor.
 3. A tobacco leaf unraveling and flattening device according to claim 2 wherein the leaf conditioning device includes a chamber having a top, bottom and first and second side surfaces, means to engage a tobacco leaf by its stem for positioning within the chamber with one side of the leaf facing the top of the chamber, the other side of the leaf facing the bottom of the chamber, and the side edges of the leaf facing the side surfaces of the chamber, a first passageway passing through the top of the chamber, a second passageway in said first side surface, and a third passageway in said second side surface whereby air is caused to enter the chamber through the first passageway and flow transversely across one side of the leaf from the stem to each of the edges and out through the second and third passageways when suction is coupled to said second and third passageways.
 4. The structure of claim 3 including a fourth passageway passing through the bottom of the chamber whereby air is caused to enter the chamber through the fourth passageway and flow transversely across the other side of the leaf from the stem to each of the edges and out through the second and third passageways when suction is coupled to said second and third passageways.
 5. The structure of claim 4 wherein said means to engage a tobacco leaf by its stem comprises a first belt having a groove in its outer periphery to engage the stem on one side of the leaf and a second belt having a groove in its outer periphery to engage the stem on the other side of the leaf.
 6. The structure of claim 1 including a belt having a groove in its outer periphery mounted between said two air permeable belts to engage the stem on one side of the leaf when said leaf is positioned on said first air permeable belt.
 7. The structure of claim 6 including means to drive said two divergent air permeable belts at the same predetermined speed and means to drive said first air permeable belt at a predetermined speed whereby the component of speed of each of the two divergent air permeable belts in the direction of travel of the first air permeable belt is at least equal to the speed of the first air permeable belt. 